When a plurality of document sheets of a particular nature common to the sheets are to be copied, the operator is required to enter the desired operational conditions for the copying of the document sheets. Such operational conditions typically include the number of the printed outputs to be produced and the reduction/magnification ratio and the print color to be used for the copying operation.
It is sometimes desired to duplicate document sheets of one nature and thereafter those of another nature. If it is desired that the two sets of document sheets be duplicated in different operational conditions, the operator is required to enter the conditions for copying operation for the document sheets of one nature and, upon completion of the copying of these document sheets, further enter the conditions for copying operations for the document sheets of the other nature. Duplication of document sheets of different natures thus requires the operator to enter the desired operational conditions for each set of document sheets having a common nature so that the operator is not allowed to leave the machine to continuously operate until the duplication of all the document sheets is complete.
Improvements have been made to eliminate such an inconvenience experienced in a prior-art image duplicating apparatus. One of these improvements is disclosed in Japanese Provisional Patent Publication (Kokai) No. 56-83754. In the image duplicating apparatus therein taught, document sheets of different natures are grouped depending on the operational conditions in accordance with which the document sheets are to be duplicated. The operational conditions to be used for these sets of document sheets are entered by the operator and stored into the apparatus for each set of document sheets. The plurality of sets of document sheets thus grouped are separated by separator plates each interposed between two sets of document sheets. Termination of the copying operation for one of these two sets of document sheets is detected through detection of the separator plate which has been present between the two sets of document sheets. Each time the presence of a separator plate is detected, the operational conditions for the copying of the next set of document sheets are read out and, copying operation is performed in accordance with the conditions thus read out. An improved version of this type of image duplicating apparatus is disclosed in Japanese Provisional Patent Publication (Kokai) No. 60-136760 in which data sheets each identifying a set of document sheets of a particular nature are used in lieu of the separator plates.
Problems still remain in prior-art image duplicating apparatus of the described types particularly in that the grouping of the document sheets to be duplicated and the use of the separator plates or data sheets require some additional jobs to be performed by the operator.